http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49110
Summary: Deferred-length character result triggers (false positive) error for pure procedures Product: gcc Version: 4.6.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: fortran AssignedTo: unassig...@gcc.gnu.org ReportedBy: jwmwal...@gmail.com The use of a deferred-length character variable as a function result triggers a (false positive) error for pure procedures. For example, the following module: module mod1 use iso_c_binding implicit none contains pure function c2fstring(cbuffer) result(string) character(:), allocatable :: string character(KIND = C_CHAR), intent(IN) :: cbuffer(:) integer :: i continue string = REPEAT(' ', SIZE(cbuffer)) do i = 1, SIZE(cbuffer) if (cbuffer(i) == C_NULL_CHAR) exit string(i:i) = cbuffer(i) enddo string = TRIM(string) end function end module mod1 When compiled, the error thrown is: ...:~$ gfortran -c test_gfortran_pure.f90 test_gfortran_pure.f90:4.4: pure function c2fstring(cbuffer) result(string) 1 Error: CHARACTER(*) function 'c2fstring' at (1) cannot be pure The module compiles just fine with ifort v12.0.4 (command line: ifort -c -stand test_gfortran_pure.f90). The version information is: ...:~$ gfortran -v Using built-in specs. COLLECT_GCC=gfortran COLLECT_LTO_WRAPPER=/usr/lib/x86_64-linux-gnu/gcc/x86_64-linux-gnu/4.6.1/lto-wrapper Target: x86_64-linux-gnu Configured with: ../src/configure -v --with-pkgversion='Ubuntu 4.6.0-3~ppa1' --with-bugurl=file:///usr/share/doc/gcc-4.6/README.Bugs --enable-languages=c,c++,fortran,objc,obj-c++,go --prefix=/usr --program-suffix=-4.6 --enable-shared --enable-multiarch --with-multiarch-defaults=x86_64-linux-gnu --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib/x86_64-linux-gnu --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.6 --libdir=/usr/lib/x86_64-linux-gnu --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-plugin --enable-objc-gc --disable-werror --with-arch-32=i686 --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu Thread model: posix gcc version 4.6.1 20110409 (prerelease) (Ubuntu 4.6.0-3~ppa1) The system information (for Ubuntu 11.04) is: ...:~$ uname -srvmpio Linux 2.6.38-8-generic #42-Ubuntu SMP Mon Apr 11 03:31:24 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux